MO844: Immune Response to SARS-COV-2 Vaccines Among Haemodialysis Patients

Abstract BACKGROUND AND AIMS Haemodialysis patients (HD) exhibit a poor immune response to vaccines. The aim of this study was to identify anti–SARS-CoV-2 spike protein antibody production following SARS-CoV-2 vaccination [1], determine variables affecting the response and compare with HBV vaccination response. METHOD Single centre prospective observational study. A total of 56 HD patients fully vaccinated for SARS- coronavirus (two doses) were followed until the day of anti–SARS-CoV-2 spike protein antibody assessment. The significance of difference was tested using either the t-test or Mann–Whitney rank-sum for continuous variables and the Chi-squared test for categorical variables. The SPSS version 22 (IBM, Armonk, NY) was used. RESULTS A total 56 patients, 62.5% males with a mean age 67.64 years and a median dialysis vintage 59 months were studied. Titers of antibodies were measured once in a median period of 138 days after the second vaccination and 76.8% of patients had a positive immune response. The same response, 76.5%, was exhibited for HBV vaccination. The age, gender, blood group, dialysis vintage, serum albumin, blood lymphocyte count, Kt/V and type of SARS-CoV-2 vaccine did not correlate with the immune response [2] (Table 1). Two females aged 81 and 50 years developed mild COVID at 140 and 118 days after the second vaccination, both with unknown antibodies at the time of infection. CONCLUSION Although the SARS-CoV-2 vaccination immune response is lower in HD patients than in the general population, it is the same as the response to HBV vaccination and from a clinical perspective it was protective against serious COVID in our population [3]. Table 1. Patients’ characteristics anti–SARS-CoV-2 spike antibodies Male gender, n (%) 35, 62.5 0.186* Age (years)—mean, [95% confidence interval (95% CI)] 67.64 (64.4–70.89) 0.133¥ Dialysis vintage (months)—median, range, IQR 59 (6, 293) 114 0.202¥¥ Blood group (n) 0.5a A 22 B 4 AB 6 0 22 Serum albumin (g/dL)—mean, (95% CI) 3.95 (3.86–4.03) 0.073¥ Blood lymphocytes (/μL)—mean, (95% CI) 1751 (1609–1893) 0.737¥ Kt/V (median, range, IQR) 1.49 (1.28–2.12) 0.27 0.13¥¥ Type of SARS-CoV-2 vaccine 0.672a Pfizer/BioNTech 51 AstraZeneca 5 Observation period (days): time (days) from second vaccination until antibody measurement (median, range, IQR) 138 (39–221) 11 0.571¥¥ SARS_Cov2_Ab_Positive, n (%) 43, 76.8 HBV vaccinated (n) 44 AUSAB positive, n (%) 39, 76.5 aFisher's Exact Test; ¥t-test; ¥¥Mann–Whitney U-te